karmada-search: Fix lock race affects watch RestChan not close, causi…

…ng client watch api to hang

Signed-off-by: xigang <wangxiang2014@gmail.com>

pkg/search/proxy/store/util.go

@@ -11,6 +11,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/watch"
+	"k8s.io/klog/v2"
 
 	clusterv1alpha1 "github.com/karmada-io/karmada/pkg/apis/cluster/v1alpha1"
 )
@@ -225,6 +226,11 @@ func (w *watchMux) Stop() {
 }
 
 func (w *watchMux) startWatchSource(source watch.Interface, decorator func(watch.Event)) {
+	defer func() {
+		if err := recover(); err != nil {
+			klog.Errorf("panic from watch source: %v", err)
+		}
+	}()
 	defer source.Stop()
 	defer w.Stop()
 	for {
@@ -246,19 +252,8 @@ func (w *watchMux) startWatchSource(source watch.Interface, decorator func(watch
 		select {
 		case <-w.done:
 			return
-		default:
+		case w.result <- copyEvent:
 		}
-
-		func() {
-			w.lock.RLock()
-			defer w.lock.RUnlock()
-			select {
-			case <-w.done:
-				return
-			default:
-				w.result <- copyEvent
-			}
-		}()
 	}
 }